#16 - Historian: We can learn about the medical history of

[donger]

My answer for the question was D. I negated D and got “mercury poisoning cannot cause deafness in people with venereal disease.” I thought this weakened the conclusion that mercury caused deafness in Beethoven. I see why my answer is wrong now because the conclusion doesn’t state mercury caused deafness but that venereal disease did. I was also misled by the example of Newton, in which his condition was caused by mercury poisoning. Is this right?

However, I can’t see why B is right. If I negate B, that means “nobody in Beethoven’s time did not ingest mercury.” I just couldn’t see how this weakened the argument or how B was a necessary assumption.

[Nikki Siclunov]

You are absolutely right, (D) is a decoy as there is no reason to believe that mercury itself was the cause of deafness: the hypothesis is that venereal disease did.

(B) is an assumption, because the logical opposite of (B) makes the argument logically absurd. Recall that the logical opposite of "some are not" is "all". So, if everyone in Beethoven's time ingested mercury, then it would be impossible for us to know if Beethoven ingested mercury to treat his venereal disease, or for some other reason. Indeed, mercury would no longer be a useful indicator of someone's medical history (this would also compromise the validity of the conclusion about Newton's psychological problems). Consequently, we would have no way of knowing if Beethoven had venereal disease, and would not be able to conclude that his deafness was caused by such a disease.

I hope this clears things up.

[GLMDYP]

Hi Powerscore!
I am confused with this question. From the stimulus, it is obvious to see that not everyone in Beethoven's time ingested mercury since not everyone had venereal disease at that time.
Is it right?
Thanks!

[Steve Stein]

In that one, the author concludes that if a trace of mercury could be found in Beethoven's hair, then that proves the hypothesis that he took mercury to treat a disease.

The question asks for an assumption on which the author's argument relies. The correct answer choice is B: to confirm that this choice is correct, we can apply PowerScore's Assumption Negation Technique: when we take away an assumption that is required by an argument, the author's argument will be weakened.

When we take away correct answer choice B, we get the following negated version:

There was no one at the time that didn't take mercury (in other words, during Beethoven's time, everyone did take mercury).

If this were the case, then traces of mercury in Beethoven's hair would prove nothing, since everyone of that time ingested mercury.

Since the negated version of this choice weakens the author's argument, that confirms this choice as the right answer to this Assumption question.

I hope that's helpful--please let me know whether this is clear--thanks!

~Steve

[lsatmike]

Is this an accurate negation of B)?

Some people in Beethoven's time did not ingest mercury -> some people in Beethoven's time ingested mercury


When negating, Do we have to negate both the quantifier (some) and the verb (did not)?

[Robert Carroll]

Mike,

The negation of a "some" is "none". In this situation, the "some" statement says that some people at the time did not ingest mercury. The negation should be "no one at the time did not ingest mercury." The double negation is awkward, so you can convert this to a more grammatical and stylistically sound form thus: "Everyone at the time ingested mercury."

Negation of quantified (some, none, not all, all, etc.) statements requires negating the quantity term used. The rest of the statement should remain untouched, unless it needs to be rephrased to sound more coherent, as above. Such a rephrasing will not change the logical features of the statement.

Robert Carroll

[Sophia123]

Hi!

I understand now why (b) is the correct answer, but I am still stumped on why (a) isn't correct. I negated this answer to say "some of the mercury introduced into the body can be eliminated." Therefore, I thought because of that negation, that even if researchers didn't find traces of Mercury in Beethoven's hair that they cannot conclusively state that he did not have a venereal disease since it is possible that some of the mercury could have been eliminated from the body.

Is there something I am missing here?

Thank you in advance!
-Sophia

[AthenaDalton]

Hi Sophia,

Your negation was correct -- if we negate answer choice (A) we are left with, "some of the mercury introduced into the body can be eliminated." Remember that "some," as the logical opposite of "none," means everything from 1 to 100 percent.

Now let's consider what this does to the author's argument: "if researchers find mercury in Beethoven's hair, they can conclude he had a venereal disease."

If we negate answer choice (A), either some (1 to 99%) of the mercury is eliminated from Beethoven's body, in which case the researchers could still find trace amounts and draw conclusions from there. Or some (100%) of the mercury would be eliminated from Beethoven's body, in which case the researchers can't make any conclusions about Beethoven's venereal disease status.

So regardless of what the researchers find, the author's argument would still be sound: that finding mercury diagnosis of disease.

The negation test is supposed to help you hone in on a foundational element of the author's argument. Here, negating answer choice (A) doesn't hurt the author's argument, so it's not the right answer.

I hope this helps!

Athena Dalton

[silent7706]

Hi,

It occurred to me that the key to solve this problem was a causal relationship in the stimulus asserted by historian, naming having VD caused Beethoven to drink mercury. The negation of (B) "All people in Beethoven's time ingested mercury" will weaken the causal relationship, because essentially it is saying without the cause (VD) (assuming most people that time did not have VD), effect (drinking mercury ) was still present. Since none of us choices otherwise weakens the causal relationship, so I ended up with (B).

I'd like to know whether my analysis was on track. Thanks in advance.

[KelseyWoods]

Hi Silent!

Great analysis and way to use that Assumption Negation technique!

Best,
Kelsey